I've been having this issue for a while when e.g. I'm watching a YouTube video in 1080p on my phone with no problems then suddenly the video stops ands starts loading, if I try to watch other videos they just won't load, but after some time it's back to normal. Or when I'm just browsing on pc (wired connection) and pages will take much longer than usual to load, but when I check my internet speed it's the average. Interestingly though, when I'm playing online games my ping never spikes. Any advice on fixing the issue or where to look for solutions?